Applications - Comtech EF Data UT-4579 Installation And Operation Manual

UT-4579 X-Band Up Converter MN/UT4579.IOM
Introduction Revision 1

1.2.1 Applications

The UT-4579 Up Converter translates the input IF frequency from 52 to 88
MHz (or optional 104 to 176 MHz) with an IF input level of -35 dBm (typical) to
an output RF frequency of 7900 to 8400 MHz and an RF output level of +10 dBm
at 1 dB compression. This permits longer cable runs and compensates for
splitting networks without requiring options such as external line amplifiers.
The phase noise performance exceeds the Intelsat phase noise mask for IBS and
IDR services by more than 9 dB. This allows high capacity earth stations to add
more demodulators and still meet transmission standards. The close-in phase
noise is also very low. This makes the converter ideal for low bit rate digital
circuits such as those used in DAMA hub earth stations.
Depending on the application, the converter chassis rear panel module slot
accepts an Input/Output Module (IOM), Receive Switch Module (RSM), Transmit
Switch Module (TSM), Polarity Switch Module (PSM), or Equalizer Module (EQM).
The converter RF, IF, and High-Speed Bus (HSB) connectors are integral to the
installed module.
Non-redundant (also called standalone or single thread) units employ an IOM for
switching the RF output. The IOM is also used for unit testing.
In redundancy applications, where converters are "Daisy Chained" to provide
distributed online protection switching to a backup converter (BU), a TSM is used
in place of an IOM. The TSM contains RF and IF transfer switches. Type 'N' female
connectors are provided for the RF loop, and 50 Ω or 75Ω BNC female connectors
are provided for the IF loop.
The "Daisy Chain" configuration is designed to chain the IF input and RF output of
up to twelve (12) online converters through TSMs terminating in a BU. When a
fault occurs in an online converter, the TSM in the faulted converter is
commanded to switch to the BU.
The BU in the "Daisy Chain" communicates with the online converters through
the installed module's High Speed Bus (HSB data interface). When faults are
detected, the BU reconfigures itself to replace the faulted online converter. The
BU also uses the HSB to monitor configuration changes made to the online
converters by either remote control or front panel command inputs.
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